CONCLUSION

Autoexhaust lead pollution contaminate the soil along the roadside. Polyalthia, Alstonia and Eugenia were found suitable for roadside plantation thereby help mitigation of lead pollution. Increase in the lead concentration in ambient air should be a cause of concern and it recalls the need for the ambient air quality standard for lead and action for effective control of autoexhaust lead pollution. Because of adverse effects of lead on the evironment in general and roadside ecosystem in particular phasing out of the alkyl lead additives in gasoline would be necessary.

ACKNOWLEDGEMENT

Authors gratefully appreciate the cooperation extended by colleges and thank Central Pollution Control Board for its permision to present this paper.

REFERENCES

• A.P.H.A. (1977). Methods: air sampling and analysis. M.Katz(Editor). American Public Health Association,Washington.
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Table 1 : Ambient air quality for lead,(ng/cu.m, 09.00 to 19.00 hrs.) at different traffic intersections in the city of Delhi during August, 1985 to April, 1987.

Sr. No.	LOCATION	TRAFFIC VOLUM ( No. of vehicles between 09.00 to 12.00 and 16.00 to 19.00 hrs.)	SEASONS						GEOMETRIC MEAN OF TOTAL OBSERVATION
			MONSOON                    WINTER                   SUMMER
			1985	1986	1985-86	1986-87	1986	1987 only April
01	TRAFFIC
	(i) DELHI      GATE	30,000 or more	426	268	332	444	283	278	245
			208-852	212-353	158-641	429-459	263-305	-
	(ii) INDIA       GATE	25,000 to 29,999	345	117	402	259	106	80	199
			185-904	81-182	218-662	231-290	93-120	-
	(iii) RED       FORT	20,000 to 24,999	572	station colsed	583	station colsed	231	station colsed	459
			366-1392		330-870		190-281
	(iv) ASHRAM	15,000 to 19,999	457	294	578	478	282	184	378
			218-668	175-707	328-1376	447-512	236-338	-
	(v) AZADPUR	Less than 15,000	341	222	411	447	221	357	310
			224-768	118-658	230-911	300-665	123-396	-
02	CONTROL LOCATION N.P.L. NURSERY	Nil	140	42	118	227	31	250	89
			125-155	30-75	48-212	225-228	225-228	-

Note: (A) @ Data based on 15, once-a-month, observations
          (B) Seasonal variation is presented as geometric mean and range of values given in the parenthesis.

Table 2 : Lead in Soil (micrograms/g) of the pots of different plant species and locations.

Sr. No.	Location	Alstonia		Eugenia		Polyalthia				Populus		Putranjiva
		May '86	Sept. '86	May '86	Sept. '86	May '86	Sept. '86	Dec. '86	Apr. '87	Dec. '86	Apr. '87	Dec. '86	Apr. '87
01	Delhi Gate	16	28	18	21	20	26	16	24	18	29	20	23
02	India Gate	14	18	22	28	17	27	12	18	14	24	16	26
03	Ashram	20	27	22	30	15	23	14	27	18	22	18	24
04	Azadpur	21	32	26	34	21	33	13	17	16	27	18	20
05	N.P.L. Nursery	12	16	14	19	13	19	11	16	14	18	15	18